Type in After Effects is a huge topic, touching on basic design, motion design, title design, effects and plug-ins, expressions, scripting, and more. CMG Hidden Gems: Chapter 21 – Textacy, new sampling of After Effects tips from Chris and Trish Meyer, covers Editing Photoshop Text, Presets in Bridge, Randomizing Order, Eases, Centering Text, Per-character 3D. Of course, tutorials and tips on the topic are extensive beyond these little gems or the ones in this week's Ten Tight Typography Tips. Here's some additional items for your consideration.
If you're looking for typographic inspiration, there are regular roundups are offered by Motion Design Love in their series Nice Type Tuesday, in the Type Tuesday series by Brad Chmielewski, and at Screenfonts (from The Font Feed), a monthly commentary on the use of fonts in movie poster design, music video and more.
There's also stuff from the Typography Gallery at Motionspire, from Topher Welsh and others at AETuts, and in the feeds of the inspiration sites aggregated by SqueezeMe.TV and the Vimeo Channels NiceType and Kinetic Typography.
General advice can be found in a great Type In Motion class resource and tumblr blog offered by Graham Huber. AE-oriented resources can be found in AE Portal posts tagged type, text, 3D text, and title design, for example see Wiggle Transform Text, Four techniques for combining fonts + type videos, and Type casting. Plug-ins are too numerous to cover in a basic survey but AE Scripts has tagged its text-oriented scripts for easy access.
And of course AE Help offers guidance in Text animation presets (see a gallery or use Bridge to preview) and Examples and resources for text animation, which is chocked full of tips and references.
Here's A Brief History of Title Design from The Art of the Title: